Characterization of Xanthoceras sorbifolium Bunge seeds: Lipids, proteins and saponins content

Abstract The increasing demand of renewable source of reduced carbon makes of interest the research on alternative oil crops. Xanthoceras sorbifolium B. is a tree that can be cultivated in marginal lands on temperate climates. This tree produces capsular fruits with seeds rich in oil containing unsaturated very long chain fatty acids that has application in cosmetics and biodiesel production. The present work focuses on the integral use of Xanthoceras seeds. Different batches of seeds were extracted and the distribution of fatty acids within the glycerol backbone was investigated by analysing the triacylglycerols species composition of the oil. Furthermore, the nuts extracted meal was characterized in terms of phospholipids content and amino acids composition. Phospholipids accounted for up to 1% of the extracted meal, displaying high levels of galactolipids and phosphatidylinositol species. The extracted meal was rich in protein (35%) with fairly high contents of essential amino acids lysine and isoleucine. Solubility studies showed albumins as the predominant protein classes in this specie. The seeds of Xanthoceras also contain saponins, active compounds present in many traditional Chinese formulations. Triterpenic and steroidal saponins were determined in different parts of the seeds, being predominant those of the triterpenic class, which were accumulated mainly in the seed hull. The possible applications of the different of Xanthoceras-derived products are discussed at the view of the results.